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Comparison of VLA batteries in tubular and flat plate designThe earliest commercially successful positive plate was the Planté plate, where the active mass is formed by a corrosion process out of the pure lead grid. This type is phasing out now, because it needs 80 – 110% more lead for the same capacity and more costly production procedures than flat, …

Exploring a methodology in costing LV electrical cable losses.IntroductionThis article looks at the long-term cost implications and ROI of sizing cable for the domestic, commercial and industrial sectors. The authors also answer the much contested question of whether power factor correction equipment is indeed a better solution than increasing cable sizing.The outcome of this sophisticated process will be a simple …

Why CHEAP is expensiveAs a new industry, everybody is still learning about LCOE (Levelised Cost of Energy) and the perils of investing in CHEAP.In most cases locally, the competitive advantage for a solar PV system is considered by comparing cost only. The bulk of consumers do not consider quality as an option, but simply price. New terminology coupled with new …

Battery voltage: Interesting factsA number of factors affect the voltage in batteries;State of chargeTemperatureAgeWhen simplified, the internal resistance of a battery will determine the battery’s voltage, which the charge controller will then use to determine whether it needs to be charging or discharging.As current moves through the cell during either charge or discharge cycles, the cell’s voltage changes as a …

MOST POPULAR COURSEBackground to labour ratesIn South Africa, labour rates for electricians are negotiated by the Electrical Contractors Association in participation with the bargaining council. These rates are amended annually and the latest rates for 2018 were published and circulated by the ECA earlier this year. For more information on the rates, negotiation process and membership with the ECA, please …

MOST POPULAR COURSEThe battery numeral systemThe sexagesimal numeral system is a place-value notation using the powers of 60 rather than the powers of 10 and this numeral system was extensively used by the ancient Babylonians, albeit without a zero (they used extra spacing instead). Although nowadays, the decimal numeral system is used extensively; like duodecimal, sexagesimal shows many vestiges in …

MOST POPULAR COURSEThe Electricity Regulation ActSchedule 2 of the Electricity Regulation Act, 2006 (ERA) defines categories of generation facilities and electricity resellers. The ERA act further provides a set of boundaries on the exemption from the requirement to hold a generation license. This document aims to provide some insight on new amendments that were published in November 2017 and is …

Johannesburg – Minister of Public Enterprises Lynne Brown gave Eskom the go-ahead on Friday to sign outstanding power purchase agreements with independent power producers who form part of SA’s independent power scheme.Brown approved Eskom’s application to purchase additional renewable energy from the producers involved in last bid windows of South Africa’s much-hailed renewable programme.“The conclusion of the power purchase agreements …

I recently had the privilege of visiting the 1,5MW rooftop PV installation at Clearwater mall being installed by Solareff. The installation was impressive and comprised of Yingli Modules, Kaco 60kW string inverters and then the Safintra S-5-PV Mounting kit. Panels are mounted at the angle of the roof which seemed to be in the region of about 8-10 degrees slope …

During the month of June; feedback from industry was the driving force behind a new perspective on the number of solar PV installations in South Africa covering both grid-tied and off-grid applications. To date, we estimated that only a few thousand solar pv (grid & off grid combined) installations had been done. This perception was challenged with the figures provided …

  Contrary to popular belief, Eskom is excited about solar PV, they have a dedicated team doing research and developing solutions for grid tied PV installations in the low voltage electrical network environment. Since the re-introduction of load shedding early in 2015, solar contractors and suppliers have experienced a significant growth in the demand for solar PV and backup energy …

How to calculate battery bank fuse sizes With the sudden increased demand in solar PV systems that would include some form of storage capacity, there are many new entrants coming into the renewable energy market, from a product supply side as well as a service & installation side. Those contractors that have been installing solar systems with battery storage for …

  The cost of aluminium has been rising steadily over the last couple of years making the decision to opt for a cheaper alternative easy when comparing the cost of mild steel as a method to support solar PV panels on rooftop and ground mount installations. Bimetallic reactions are hardly ever mentioned in conversations where supporting mechanisms are discussed. The …

The form attached to this post, is a draft version and has been circulated for comment or feedback from industry. Distribution and or circulation of an application form for solar PV installations is long overdue. So use the form as the basis of information that may be required when grid tied PV systems are being done. Information relevant to the …

Eskom Grid areas for Solar PV Who to contact at Eskom with regards to grid tied solar PV systems. Quite regularly during training sessions, contractors and engineers would enquire about the contact details and procedures to follow when applying to have a solar PV system connected to the grid. With more than 270 municipalities and only a handful of them …

Although the installation of PV systems, especially rooftop PV systems have been increasing in demand and volume of installation, very few contractors are concerned about the lightning protection system that should form part of the PV rooftop installation. The new SANS10142-3 standard being developed; is aimed at providing some guidance with regards to the installation standard for embedded generation. Due …

The graph above provides a breakdown of the different sized PV systems that companies have installed. This is relevant as it indicates or could indicate a certain trend in the growth of organisations involved in the solar PV sector. As an example, most companies seem to do smaller installations and then grow into larger projects. There are however the “exceptions” …

PV industry growth and demand – South Africa The most extensive list of privately owned installed and commissioned pv systems  in SA has seen significant growth since Jan 2015. The ongoing list is being created with a number of goals in mind. Showcasing local privately owned solar PV installations Data collection Monitoring growth and development of the sector Understanding the PV …

Backup and Off Grid Battery Packs Using Superior Lithium Iron Phosphate (LiFePO4) Cells – the next Generation of Energy Storage By: Antony J English, Co-founder of Freedom Won Pty Ltd The rate of adoption of Lithium Iron Phosphate (LifePO4) batteries as a mainstream storage solution for alternative energy systems in Europe and some other parts of the world is not …

With more than 30 locally available grid tied inverters to choose from, how do local contractors know which ones to install? Where would a local installer or contractor even begin to start looking for suppliers, brands and models of inverters and other solar equipment. In a recent post, circulated earlier today; we looked at the limitations that should be considered …

Recently numerous articles have been circulated showing very good looking residential installations where the contractors have installed fair sized pv systems of which most have been grid tied. In the absence of standards most contractors have been installing systems sized according to the consumption patterns of the consumer. It should be noted that there is a standard that guides installers …

This graph has been made available by Karin Kritzinger – Centre for Renewable and Sustainable Energy Studies, and indicates how PV and Wind Power has been supporting the grid. Red on the graph shows the addition of PV power from the various utility scale REIPPP programs and the blue shows when wind power resources start coming online. It may be …

The most comprehensive and up to date list of privately owned PV installations in SA contains more than 250 solar installations producing a total 27656kWp or 27MWp; the equivalent of a utility scale PV power station. More than 45 listed contractors. The table above shows the top 40 contributors to the list along with each organizations’ total listed installations indicated …

So before we start, where does the data come from and how do we even know that it could be accurate. Data used was taken from a list of PV systems that includes a little more than 253 installations generating just over 27MW’s worth of electricity. (The list can be seen by following the link provided at the end of …